Review of Factors Contributing to Nodular Goiter and Thyroid Carcinoma.

There is an increased incidence of thyroid nodules and cancer. In this article, the reasons for this increase are evaluated and discussed. The factors causing increases in the incidence of nodules are the same as those causing increases in thyroid cancer. There are publications from all over the world regarding the rising incidence of thyroid cancer; it is especially associated with papillary cancer. The literature was reviewed and evaluated with regard to this significant phenomenon. Thyroid-stimulating hormone (TSH) is the main mitotic factor. Any agent that elevates TSH will stimulate nodule formation. Therefore, the incidence of thyroid nodules is high in endemic goiter regions due to iodine deficiency. This paper has described many of the factors causing this higher incidence. Of note, metabolic syndrome and insulin resistance are important factors associated with the increased incidence of nodular goiter and papillary thyroid cancer today. However, these data must be confirmed by other studies in the future.